Question

2. For each day that Sasha travels to work, the probability that she will experience a delay due to traffic is 02. Each day can be considered independent of the other days. (a) For the next 21 days that Sasha travels to work, what is the probability that Sasha will experience a delay due to traffic on at least 3 of the days? (b) What is the probability that Sasha's first delay due to traffic will occur after the fifth day of travel to work? (c) Consider a random sample of 21 days that Sasha will travel to work. For the proportion of those days that she will experience a delay due to traffic, is the sampling distribution of the sample proportion approximately normal? Justify your answer. Please respond on separate paper, following directions from your teacher

Answer 1

solution: m=21 p=0.2 xn Binomial P(x) = () 8²9 x I P( x3): 1- $ P(x=0) + P(x=1) + P(x-2)} 21-* =1 - 1)(0.23 (0-8) - 1 - 0.1787 = 0.8213 b) yn Geometric p = 0.2 Ply) = q4-1p Ply=5) = (0.85 (0:2) I 5-1 = 70.0819 n=21 p = 0.2 np = 21x0.2 = mq = 2 21xo.8 = 4.2 16.8 since, npcs sampling is distribution of sample proportion Not T Normal.